title: (2,2'-Bipyrid-yl-κ(2) N,N')bis-(η(5)-penta-methyl-cyclo-penta-dien-yl)barium.
abstract: In the title compound, [Ba(C10H15)2(C10H8N2)], the Ba-N distances are 2.798 (3) and 2.886 (3) Å, and the Cp ring centroid distances to Ba(2+) are 2.7291 (7) and 2.7192 (9) Å. The angle between the N atoms in the bypyridine ligand and the metal ion is 56.80 (8)° and the N-C-C-N torsion angle in the bi-pyridine ligand is 1.7 (4)°. The bi-pyridine ligand is almost planar, the dihedral angle formed by the intersection of the planes defined by the pyridyl rings being 3.04 (19)°, and the angle between the plane defined by the Ba(2+) ion and the two bipyridyl N atoms and the plane defined by the 12 atoms of the bi-pyridine ligand is 10.2 (3)°. The average Ba-N and Ba-centroid distances are 0.16 and 0.14 Å longer, respectively, than the equivalent distances in the isotypic strontium compound [Kazhdan et al. (2008 ▶). Acta Cryst. E64, m1134]. This difference is in accord with the difference between the ionic radii of 0.16 Å suggested by Shannon [Acta Cryst. (1976 ▶), A32, 751-767].
authors.affiliation: Chemistry Department and Chemical Sciences Division of Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Kazhdan
authors.forename: Sergio S
authors.initials: SS
authors.lastname: Rozenel